media: videobuf2: Fix length check for single plane dmabuf queueing

Check against length in v4l2_buffer rather than vb2_buffer when the
buffer is a dmabuf. This makes the single plane test the same as the
existing multiplanar test.
Signed-off-by: John Cox <jc@kynesim.co.uk>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/common/videobuf2/videobuf2-v4l2.c

@@ -117,7 +117,8 @@ static int __verify_length(struct vb2_buffer *vb, const struct v4l2_buffer *b)
 				return -EINVAL;
 		}
 	} else {
-		length = (b->memory == VB2_MEMORY_USERPTR)
+		length = (b->memory == VB2_MEMORY_USERPTR ||
+			  b->memory == VB2_MEMORY_DMABUF)
 			? b->length : vb->planes[0].length;
 
 		if (b->bytesused > length)